class Solution {
public:
    int minPathSum(vector<vector<int>>& grid) {
        int m = grid.size(), n = grid[0].size();
        vector<vector<int>> dp(m, vector<int>(n, grid[0][0]));

        for (int i = 1; i < n; i++)
            dp[0][i] = dp[0][i - 1] + grid[0][i];
        for (int j = 1; j < m; j++)
            dp[j][0] = dp[j - 1][0] + grid[j][0];

        for (int i = 1; i < m; i++)
        {
            for (int j = 1; j < n; j++)
            {
                dp[i][j] = grid[i][j] + min(dp[i][j - 1], dp[i - 1][j]);
            }
        }

        return dp[m - 1][n - 1];
    }
};